Western Digital Purple PR1000M, Technical Reference Manual

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PR1000M
ATA C
OMMAND
S
ET
2679-800020-A03 RELEASED 5/8/17 (WD CONFIDENTIAL) 27
4.1.4 SCT Commands
SCT commands provide capabilities not covered in ATA/ATAPI-7 for commands that
do not fit the ATA command delivery model. Some SCT commands report completion
when the command begins execution. Execution progress for these commands may
be checked by requesting SCT status. For instance, the host can track the progress of
a Write Same command by issueing a status request once per minute. See ATA8-ACS
for a full description of SCT.
Table 4-4. SCT Action Codes
4.2 S.M.A.R.T. (B0h)
The S.M.A.R.T. command provides access to attribute values, S.M.A.R.T. status, and
other S.M.A.R.T. information. These commands can be used for logging and reporting
purposes, and for accommodating special user needs.
Prior to writing the S.M.A.R.T. command to the Command Register, the host must
write key values into the LBA Mid and LBA High Registers (4Fh, C2h) or the command
will be aborted and an error will be reported.
The S.M.A.R.T. command has several sub-commands that are selectable via the
Features Register when the host issues the S.M.A.R.T. command. To select a sub-
command, the host must write the appropriate sub-command code to the Features
Register before issuing the S.M.A.R.T. command. The sub-commands and their
respective codes are listed below. For more detailed information on executing
S.M.A.R.T. commands, see the ATA-7 specification.
4.2.1 Read Attribute Values Sub-Command
This command returns a sector of data with the drive's S.M.A.R.T. data structure.
Table 4-5. Definitions for the 512 Bytes.
ACTION CODE DESCRIPTION
0000
H
RESERVED
0001
H
O
BSOLETE
0002
H
W
RITE
S
AME
0004
H
F
EATURES
C
ONTROL
0005
H
SCT D
ATA
T
ABLES
0006
H
V
ENDOR SPECIFIC
0007
H
SCT BIST
C000
H
FFFF
H
V
ENDOR SPECIFIC
BYTE VALUE DESCRIPTION
0 - 1 0001
H S.M.A.R.T. Data Structure Revision
2 -361 XX
S.M.A.R.T. Attribute Data
135 - 361 XX
S.M.A.R.T. Attribute Data
362 XX
Offline data collection status
0Xh OL disabled
8Xh OL enabled
X0h scan not run
X2h scan complete
X4h scan suspended
X5h scan aborted
363 XX
Self-Test execution status byte.